The present invention relates generally to air dams for use below the front ends of automotive vehicles.
In order to improve fuel economy at high speeds, some automotive vehicles employ air dams mounted below the front end of the vehicle. The lower ground clearance at the front end created by the air dam improves the aerodynamic drag on the vehicle at high speeds, thus improving fuel economy. These air dams are typically fixed in position. The tradeoff for the positioning of the air dam above the ground (i.e., ground clearance) is between a low height, the lower they are to the ground the better the aerodynamic drag at high speed, and a higher height off the ground, which protects the air dam from being damaged by contact with a curb or parking lot block when parking the vehicle.
To overcome this tradeoff, some have replaced the fixed air dam with a moveable, active air dam that is automatically moved up and down via a motor and linkages controlled by an electronic controller. In this way, the controller can monitor the speed of the vehicle and activate the motor to move the air dam down (lower ground clearance) at higher vehicle speeds and lift it back up when the vehicle slows down. This provides lower ground clearance of the air dam for improved aerodynamic drag at higher vehicle speeds while also providing a higher ground clearance for the air dam when parking the vehicle in order to minimize the chances of damaging the air dam when parking the vehicle.
However, the high cost of the motor, linkages and controller make active air dams too expensive to use on some models of automotive vehicles. Moreover, a potential for warranty cost increases exists due to the fact that a motor, linkage and wiring is packaged low and at the front of the vehicle, potentially exposing it to damage from the environment around the vehicle. These active air dam systems may also add more weight to the vehicle than is desirable.